Sensors are usually either optical or electronic. Conventional optical sensors rely on materials that change colour according to analyte levels. This is an economical approach for measuring coarse analyte levels, but with the need for higher resolution, colour differentiation between fine analyte levels becomes challenging. To obtain higher resolution sensing, conventional electronic sensors usually measure the generated electrochemical potential or physical electrical signals. However, such conventional electronic sensors would require a high input impedance circuit for signal acquisition because the electrical signal generated is usually very low (e.g., less than 100 mV). Therefore, such conventional electronic sensors have been found to require a sensor front-end and a signal measurement/processing back-end. The front-end can be made low-cost by printing sensor materials on paper or plastic. However, the back-end signal measurement/acquisition circuits, due to their need to measure very low voltages, are nevertheless based on traditional electronics. Therefore, although such conventional electronic sensors may yield a low-cost front-end sensor, they still require a relatively expensive back-end signal measurement and display device. As a result, the need for a back-end signal measurement/acquisition device in such conventional electronic sensors renders high resolution sensing still relatively expensive for low-cost applications.
A need therefore exists to provide a sensing device for measuring a level of an analyte, and a method of fabrication thereof, that seek to address or at least ameliorate one or more of the problems associated with conventional electronic sensors. It is against this background that the present invention has been developed.